CIS 102 – Fall 2009

Midterm Exam 2 Study Guide

Format: Open book, open notes, open PC, multiple choice, approximately 25-30 questions, exam taken through Moodle with time limit of 60 minutes.

Study materials:

PowerPoints:

Data Types

Number Systems

Data Representation

Selection

Repetition

Reading Material – Introducing Small Basic pdf Ch. 4 & 5 (not Goto or branching)

Handouts – Activity 3, Activity 4, Activity 5, and ASCII Chart

Assignments – Assign 3 and Assign 4

Quizzes – Quiz 2 & 3

Topics :

Data Types

• Types of program data
•  Program data elements – variables, constants, literals
•  Program data types – integer, floating point, character, Boolean, string
•  Identifiers – make their names meaningful
•  Format for variables
•  Format for constants

Number Systems

• Value vs representation
• Decimal, binary, and hexadecimal
• Positions have weights – powers of 10, 2, and 16
• Different numbers systems are used in computing

Data Representation

·  Bit patterns

·  Binary numbers

·  Data type formats

·  Character representation – ASCII Chart

·  Integer representation – unsigned integer, signed positive integer, signed negative integer (two’s complement)

•  Floating point number representation – sign, exponent, mantissa

Selection

·  Review sequence control structure

·  Structure theorem – sequence, selection, repetition

·  Selection control structure

·  If statement

·  Relational operators – <, >, =, <=, >=, <>

·  Types of selection – simple, null else, combined (And & Or)

·  Structured programming

·  Truth tables

Repetition

·  Review sequence and selection

·  Repetition control structure

·  While loops

• Sentinel value
• Priming the loop
• Infinite loops
• Input validation
•  Small Basic Text object like toolbox

·  For loops

·  Structured programming

·  Hints for defining the problem – descriptive words (nouns) & action words (verbs) help with defining input/output and processing